ERIC ED364422: Atmospheric Detectives. Atlas 2 Teacher's Guide with Activities.

28 Pages·1992·0.75 MB·English

by  ERIC

DOCUMENT RESUME
ED 364 422
SE 0!,3 920
TITLE Atmospheric Detectives. Atlas 2 Teacher's Guide with
Activities.
INSTITUTION National Aeronautics and Space Administration,
Washington, DC. Educational Affairs Div.
REPORT NO NASA-EP-285/11-92
PUB DATE
92
NOTE
28p.
AVAILABLE FROM
Education Division, NASA Headquarters, Code FET,
Washington, DC 20277-2028.
PUB TYPE
Classroom Use - Teaching Guides (For
Guides
Teacher) (052)
EDRS PRICE MF01/PCO2 Plus Postage.
DESCRIPTORS
Air Pollution; *Climate Change; Concept Formation;
*Earth Science; Elementary School Students; Global
Warming; Intermediate Grades; Junior High Schools;
Junior High School Students; Measurement;
Meteorology; Middle Schools; Physical Sciences:
*Science Activities; Science Curriculum; Science
Education; Scientific Concepts; Space Sciences;
Spectrescopy; Teaching Guides; Weather
IDENTIFIERS
*Atmospheres; Middle School Students; Ozone
Depletion
ABSTRACT
As part of the National Aeronautics and Space
Administration Mission to Planet Earth, ATLAS 2 will help develop a
thorough picture of the Sun's output, its interaction with the
atmosphere, and the well-being of Earth's middle atmosphere. This
middle school level guide probes the connection between the
activities of scientists and the observable world of weather and
climated. To do this, the guide is divided into four sections. The
first section, "Case History: What ATLAS 1 Discovered" summarizes the
findings of the ATLAS 1 Spacelab/Shuttle flight of March 1992. It
links that mission with the science goals of ATLAS 2 and future
flights. The second section "The Search: What ATLAS 2 Scientists
Investigate" delves into the invisible world of protons, neutrons,
and electrons to explain the fundamental mechanism of absorption of
ultraviolet radiation by ozone and the destruction of ozone by
chlorofluorocarbons. The third section "The Motive: How Solar and
Atmospheric Changes Might Affect Climate" explores the relationship
between solar activity and weather and climate. The fourth section
"The Method: How Atlas 2 Investigators Make These Measurements"
studies the remote-sensing techniques of spectrometry and limb
sounding. It also involves students in ground-truth studies and
exercises that emphasize the importance of mathematics and precise
measurement. (PR)
***********************************************************************
Reproductions supplied by EDRS are the best that can be-made
from the original document.
***********************************************************************
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INLAS 2 Teacher's
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FOR USE WITH MIDDLE-SCHOOL STUDENTS
U.S. DEPARTMENT Of
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EDUCATIONAL RESOURCES
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BEST COPY AVAILABLE
Atmospheric Detectives
ATLAS 2 Teacher's Guide
with Activities
For use with middle-school students
Contents
Preface
Crew Biographies
ii
Instructions for Using the Teacher's Guide
iii
Case History: What ATLAS 1 Discovered
iv
The Search: What ATLAS 2 Scientists
Investigate
1
Case No. 1 - Why study the atmosphere/
1
Case No. 2 - Why study the Sun/
4
The Motive: How Solar and Atmospheric
Changes Might Affect Climate
6
Case No. 1 - How could changes in the Sun
affect climate/
6
Case No. 2 - What does wind have to do
with weather?
8
Case No. 3 - What are the roles of water
vapor?
10
The Method: How ATLAS 2 Investigators
Make These Measurements
12
Case No. 1 - How can we measure from
a distance?
12
Case No. 2 - How can scientists be
sure their measurements are accurate?
14
Answers
16
Glossary
17
Appendix: Resources
18
Preface
Can you imagine doing a science project in
space? This is the challenging and exciting
situation that
researchers experience in Spacelab, the laboratory
carried inside the Shuttle. Here, hundreds of
kilometers
above Earth's surface, the
crews of the ATLAS missions scan, probe, and
measure concentrations of chemicals
and water vapor in Earth's protective bubble.
So far, one ATLAS crew has rocketed into the
atmosphere,
watching many sunrises and sunsets
come and go while active:ng delicate instruments and
conducting
experiments that monitor the complicated
interactions between the Sun, the atmosphere, and
Earth.
We, the crew of ATLAS 2, will continue this
important work aboard the Space Shuttle. Together,
we will gather
data that will be compared with information
from satellites, balloons, and instruments
on the ground. As part of
the National Aeronautics and Space
Administration's (NASA's) contribution to Mission
to Planet Earth, ATLAS 2
will help develop a thorough picture of the
Sun's output, its interaction with the atmosphere,
and the well-being
of Earth's middle atmosphere.
Because the health of the atmosphere is of vital
importance to all Earth's inhabitants,
everyone should be part of
this investigation. You can be active
participants in exciting and vital activities: recycling
and practicing other
conservation methods and gathering information
to learn more about how you can keep
our atmosphere
healthy now, as students, and in the future
as informed citizens, scientists, technicians, and mathematicians.
3
ATLAS 2 Crew
Ken Cameron
idea that our
unique vantage point that reinforces the
Flying the Space Shuttle on orbit offers the crew a
study the Shuttle's
of 5 billion people. Just as the astronauts
planet is really a spacecraft itself, with a crew
atmosphere, and our
Earth all need to learn more about our planet, its
systems to learn to fly it safely, we on
pleased and
safely and successfully for a long voyage. I am very
Sun's influence on it in order to pilot it
spacecraft Earth.
honored to be a part of this mission to study
Stephen Oswald
E NASA
especially gratifying to
Shuttle is an extraordinary privilege, but it is
Any opportunity to fly aboard the Space
data on the
which promises to benefit all of humanity. Gathering
be participating in the ATLAS 2 mission,
should
atmosphere is precisely the kind of job that NASA
interrelationship betweerithe Sun and our fragile
the
ATLAS 2 could prove to be of tremendous importance to
be doing and to which the Shuttle is best suited.
of the team.
long-term health of our planet, and I'm glad to be a part
Mike Foale
planets is one
and spaceflight. The possibility of exploring other
As a child, I was always intrigued by flying
subjects
could have. Science and mathematics were natural
of the most exciting opportunities our generation
dreams
Cambridge University. With that background, my
for me to study at school, especially physics at
the Earth's terminator
enough to fly on ATLAS 1. The sunrises and sunsets,
were realized when I was lucky
of Earthl, and the aurora were some of the most
[the dividing line between the sunlit and dark portions
beautiful sights
gives me a wonderful chance to see such
beautiful views I have ever seen. Flying on ATLAS 2
the scientific puzzle of our planet's climate.
all over again and to add yet another piece to
Ellen Ochoa
school. While I
the Moon the summer before I started junior high
I remember watching Apollo 11 land on
I just
occurred to me that I could grow up to be an astronaut. I guess
was fascinated by the event, it never
special group of people very different from me. But space
assumed that exploring space was limited to a
interested in learning new subjects, investigating
exploration is a field that is open to anyone who is
interest in math led me to study physics in
mysteries, and working hard to achieve goals. In my case, my
graduate school and a career in research. It wasn't
college, and my interest in solving problems led me to
that NASA
about the astronaut selection process and realized
until I was in graduate school that I found out
and a challenge to try to do my best in
That was a wonderful surprise
was looking for people like me.
and to have been
goal. I feel very lucky to have been chosen as an astronaut
school and at work in order to achieve such an exciting
scientific research
incredible opportunity for me to be involved in an important
selected for the ATLAS 2 mission. This flight is an
affect our atmosphere.
effort to understand how both the Sun and human activities
Ken Cockrell
childhood memories is of an airplane flying over my backyard.
I have always wanted to fly. One of my first
has never gone away. In school, I chose courses in math
That little event sparked a desire in me to fly that
for a flying career. After college, I joined the Navy and
and science and an engineering degree to prepare
tremendous fun to fly each new type of airplane that
flew jet fighters from aircraft carriers for 15 years. It was
excited about
the new "airplane" is the Space Shuttle, and I'm more
came along during those years. Now
the greatest flying machine ever built. On ATLAS 2,
flying it than I've ever been before. To me, the Shuttle is
atmosphere and to better understand the changes in the
the Shuttle enables us to study the changes in our
proud
the Earth's fragile environment in the future, and I'm
Sun's energy. This knowledge may help us protect
to be a part of the effort.
INSTRUCTIONS FOR USING THE TEACHER'S GUIDE
The ATLAS 2 Teacher's Guide
/ blends lessons in mathematics, chemistry, physics, and Earth science
/ nurtures students' natural curiosity and excitement about science and technology
/ encourages students to see their questions as the seeds of careers in science, mathematics, and technology
/ fosters creative and critical thinking and problem-solving skills
supplements the ATLAS 1 Teacher's Guide, Earth's Mysterious Atmosphere (NASA publication EP-282).
The ATLAS 2 Teacher's Guide probes the connection between the activities of scientists and researchers and the observable world of
weather and climate. To do this, the guide has been divided into four sections:
I. Case History: What ATLAS 1 Discovered briefly summarizes the findings of the ATLAS 1 Spacelab/Shuttle flight of March
1992. It links that mission with the science goals of ATLAS 2 and future flights.
II. The Search: What ATLAS 2 Scientists Investigate delves into the invisible world of protons, neutrons, and electrons to
explaio the fundamental mechanisms of absorption of ultraviolet (UV) radiation by ozone and the destruction of ozone by
chlorofluorocarbons (CFCs). It also explains why ATLAS scientists study the Sun's energy.
Ill. The Motive: How Solar and Atmospheric Changes Might Affect Climate explores the relationship between solar
activity and weather and climate. Specifically, this section looks at solar output, wind patterns, and water vapor.
IV. The Method: How ATLAS 2 Investigators Make These Measurements studies the remote-sensing techniques of
spectrometry and limb sounding. It also involves students in ground-truth studies and exercises that emphasize the importance of
mathematics and precise measurement.
The guide may be taught in its entirety, or you may choose to teach particular sections. You may even want to choose among the
cases in each section. Cases and sections are designed to stand alone; the ideas contained in them do not depend on the rest of the
guide.
The science concepts in the ATLAS 2 Teacher's Guide have been designed to complement the middle-school (grades 6, 7, and 8)
curriculum; however, many activities may be used with younger and older students. You may adapt the guide to your students'
needs and interests.
All sections follow the format of a detective case.
Cases: Several cases appear in each major section. These are in the form of questions that student detectives might ask about the
atmosphere
its functions, possible damage or changes, and causes and solutions.
Clues: These precede investigations and contain important background information for teachers and students.
Investigation: These hands-on activities focus and extend information in the Clues section. There are two
investigations per case. You may use one or both as teaching activities or reproduce them and assign as tasks to
small groups.
Materials: This section lists the materials needed to perform the investigation. Household items are used
whenever possible.
Procedure: This provides detailed instructions and cautions. Before beginning any procedure, encourage students to
formulate hypotheses about what they think will happen.
Questions: Answers to most questions are found at the end of each of the four major sections. Some are open ended
to stimulate creative thinking. Encourage students to support creative answers with what has been observed in the
Investigation or learned in the Clues sections.
Relating Science to
... These sections provide suggestions for group or individual activities in other areas of study,
such as art, literature, math, music, and social studies.
Helping Mother Earth: These facts and classroom discussion ideas extend the guide's scope beyond ATLAS'
atmospheric research to include other areas of concern in the environment. Students may work
on these activities in
school or at home.
III
Case
History:
What ATLAS 1 Discovered
a small copy of an airplane, a car, ship, or spacecraft? Toy
Have you ever put together a model
manufacturers try to make their models as much like, the original object as possible. Model cars have
the same tires, the same color paint, and the same decorations as real cars. In a similar way, scientists
studying the atmosphere create models. Using mathematics instead of wood, plastic, and rubber
parts, they try to show how wind currents, the oceans, the Sun, and elements and compounds in the
atmosphere interact, and how they are affected by humans. If you make a model car, you may be
able to compare it with a real car to check its accuracy. Researchers chock the accuracy of their
mathematical models by comparing predictions with actual observations. To do this, they measure
natural and manufactured chemicals in the atmosphere, wind currents, sunlight, and many other
factors to determine if what they thought should be there is actually there. Using models in this way,
researchers can understand past and present events and possibly predict future occurrences.
The ATLAS 1 Spacelab mission, which flew in March 1992, acquired some of the important
information needed to check existing models and develop new ones. The huge amount of data
collected includes the measurement of many trace gases in the middle atmosphere. One very
interesting result was the observation of a layer of tiny droplets of sulfuric acid and water in the
atmosphere. These small, floating particles called aerosols resulted from the eruption of Mount
Pinatubo in the Philippines in 1991. The aerosol layer was so thick that some of the ATLAS
instruments could barely measure through it. Observers on future missions will be studying this layer
to see how much it has diminished and if it still has any effect on the ozone that exists at about the
same altitude. Other researchers have also been checking surface temperatures and sunlight
measurements from the ground. They will use these data in mathematical models to determine
whether this aerosol layer has shielded Earth from some of the Sun's heat.
ATLAS 1 scientists found that amounts of some chlorofluorocarbons in the atmosphere had doubled
since 1985. These atmospheric detectives also measured amounts of a substance called hydroxyl.
This chemical "eats" ozone in the mesosphere in much the same way that chlorine compounds
destroy ozone in the stratosphere. The scientists also measured water vapor, which acts as a
greenhouse gas. ATLAS 1 instruments also recorded important information on ozone that will help
researchers understand how ozone behaves in the stratosphere. ATLAS 1 measurements were made
primarily in the Southern Hemisphere. If it is launched in the spring, ATLAS 2 will concentrate on
measurements in the Northern Hemisphere.
Another goal of ATLAS 1 scientists was to study the total radiation traveling from the Sun to Earth's
atmosphere. They accomplished this goal and at the same time analyzed particular wavelengths of
sunlight that could affect our atmosphere, such as ultraviolet, visible, and infrared. Light
measurements will be carefully compared with past and future information to decide whether the
total solar radiation is changing.
It will take many years to analyze the ATLAS 1 data. In the meantime, data from ATLAS missions, the
Upper Atmosphere Research Satellite and other spaceborne instruments, and ground measurements
will be collected and studied. Atmospheric detectives all over the world will be working to learn
more about our planet, our star, and the enormous, complicated system that connects them. You can
be an important part of that team. Let's juin them!
iv
The
Search:
What ATLAS 2
Scientists Investigate
or
Case
Why study
No. 1
the atmosphere?
CLUES:
What things are most valuable? Diamonds? Gold? Air? Although we can't measure its value in dollars, Earth's
atmosphere is also precious, for without it, life on Earth would not exist. Our bubble in space provides air to
breathe, regulates the Sun's energy to heat and cool our planet, and filters the Sun's rays, allowing those that.
provide heat and light to reach Earth's surface while blocking those that are deadly.
Scientists are concerned because the amounts of some chemicals in our atmosphere are changing. Gases
released by industry and agriculture are building up in the lower atmosphere and could enhance the
atmosphere's warming influence, perhaps leading to temperature changes with long-range effects. Ozone, a
part of the stratosphere that acts as a natural screen for dangerous ultraviolet (UV) radiation, is being destroyed
by other human-made compounds. In 1992, concentrations of this gas over the Antarctic reached their lowest
levels since measuring began in the 1960s. Scientists estimated an area of depleted ozone in the Antarctic that
is larger than the United States and deep enough to hold Mount Everest. If the depletion of the ozone layer in
the stratosphere continues, increases in UV radiation reaching Earth's surface would be a serious concern.
Plants and animals would be affected. Even the tiny ocean organisms that remove carbon dioxide from the
atmosphere might be destroyed, possibly increasing concentrations of this greenhouse gas in the atmosphere
and raising temperatures. Also, these organisms serve as the base of oceanic food chains, and changes in their
populations could have serious environmental consequences.
Researchers have also wondered if the Sun's output is changing, leading to temperature or other atmosphere
changes on Earth. What will be the outcome of all these changes? Scientists form theories but cannot be
sure.
These are mysteries; there are many clues but no definite answers yet.
To investigate these mysteries, ATLAS 2 scientists will continue to measure the gases in the middle atmosphere
(stratosphere and mesosphere) and monitor the output of the Sun.
7
Investigation A: Building Gases
Scientists working on ATLAS 2 measure many familiar gases in the atmosphere, such as ozone, carbon
monoxide, carbon dioxide, water vapor, and methane. They also measure less well-known gases such as
chlorine monoxide and nitrogen compounds.
To understand the importance of these gases in the atmosphere, you must first know something about the
structure of the molecules and atoms that make up these gases. Atoms, originally thought to be the smallest
particles making up an element, are actually composed of protons, neutrons, and eledrons. Protons are
particles carrying a positive electric charge (+), and neutrons have no electric charge. Protons and neutrons
form the nucleus, or center, of the atom. Electrons, which carry a negative charge (), revolve around the
nucleus in a kind of eledron cloud. Low- energy electrons move around close to the nucleus, while high-
called shells.
energy electrons speed around the outside levels of the cloud. These levels are sometimes
Atoms can gain, lose, or share electrons. When atoms share electrons, bonds form between them, and they
become molecules. Molecules may be composed of atoms from the same element or atoms from different
elements. For example, oxygen molecules (02) are made of 2 atoms of oxygen, but water molecules (1-120) are
made of 2 atoms of hydrogen and 1 atom of oxygen. The small number to the right of the chemical symbol tells
how many atoms of each element are in the molecule.
Atoms of oxygen (0) tend to gain electrons. They may also share electrons with other oxygen atoms, forming
molecules of oxygen (02) or ozone (03). In the stratosphere, ozone protects plant and animal life by absorbing
harmful ultraviolet (UV) rays. !n the troposphere, ozone is not so helpful. It is a major ingredient in smog, which
damages plants and endangers humans and other animals. Try making this model to help you visualize the
formation of ozone, this gas that can be helpful or harmful.
Materials Needed:
4 white marshmallows
./ toothpicks
Procedure
The mrshmallows represent atoms of oxygen, and the toothpicks represent the bonds between them. Use one
toothpick to join two marshmallows. Repeat the process with the other two marshmallows. You now have a
model of two molecules of 02 as it usually exists in the lower atmosphere.
In the stratosphere, UV radiation is absorbed by 02 molecules. This extra energy breaks the bond between the
two atoms. Pull apart one pair of atoms to show the breaking of the bond. These oxygen atoms are now free to
join with other 02 molecules, forming 03, or ozone. If you join one free marshmallow to a pair, you will have
a model of 03 and can see that there is still another oxygen atom ready to create more ozone.
Questions
0 What do you think happens to the amount of UV radiation
litialinstMotherlarth
reaching Earth when ozone is destroyed?
Trees take in carbon
dioxide, one of the
major greenhouse
gases, and use it and
water to make food
(a form of sugar).
In return, they give us the oxygen we
breathe. To help reduce greenhouse gases,
it is important that we cut down fewer
trees. To accomplish that, we must use less
paper. Help your family start a "rag bag."
collect old clothes that can be used
In
to clean up around the house, washed,
and used again. This will save paper
towels for °throw away" messes only.
2
Investigation B: Out Goes the Ozone
Chlorofluorocarbons (CFCs) are compounds used mainly as coolants in refrigerators and air conditioners.
When CFCs escape, they are mixed by air motions in the atmosphere and transported into the stratosphere.
There, they absorb UV radiation. This extra energy breaks the bonds holding these compounds together,
releasing an atom of chlorine. The chlorine atom then pulls away the third oxygen atom in ozone, breaking
the weak bond that joins it to the rest of the molecule. This destroys an ozone molecule and forms
a molecule
containing one atom each of chlorine and oxygen that also has weak bonds, making it unstable.
Because the chlorine-oxygen molecule is unstable, it is easy for free atoms of oxygen (0) to pull away the
oxygen atom, forming 02
and releasing the chlorine to destroy more ozone. This process and slightly more complicated
ones are what is depleting the
protective "ozone umbrella" in the stratosphere. The chlorine is not used up, and it can continue to destroy ozone.
Make these models for a "bite-size" view of the reactions between CFCs and ozone.
Materia le Needed:
bag of jellybeans, gumdrops, or other soft, multicolored candy
.1 box of toothpkks
Procedure
One of the simplest CFC molecules is CFCI3. It has one atom of carbon, one atom of fluorine, and three atoms
of chlorine. To make a model of a molecule of CFCI3, use three pieces of green candy to represent chlorine,
one black piece to represent carbon, and one red piece to represent fluorine. Because the fluorine and carbon
atoms are smaller than the chlorines, cut the biack and red candies in half, and keep only half of each.
Toothpicks will represent the bonds between the molecules.
Stick three toothpicks into the piece of black candy, forming a three-legged stool with the legs evenly spread.
Attach a green candy to the free end of each toothpick. Stand the stool on the desk and gently push down
on the piece of black
candy until the green pieces have slid apart enough that the black candy is suspended about 2 inches above the table. With
your
stool sitting on the table, insert a toothpick vertically in the top of the black candy and attach the red piece to the free end
of the
toothpick. This is a rough model of a CFCI3 molecule. Lay it aside until later.
Use three pieces of white candy (representing atoms of oxygen) to create a model of ozone. Use two toothpicks to connect them,
forming a triangle. Get an extra white piece and keep it handy for use later.
Lay your model of CFCI3 and your model of ozone on a
sheet of clean paper. When UV radiation hits a CFC
molecule, the molecule releases chlorine. Pull off one green
piece of candy from the CFCI3 model to show this process.
(
The free chlorine atom destroys an uzone molecule by
attracting one of the oxygen atoms away from the ozone
1 it 41\
molecule. Remove one of the white pieces of candy and its
I,
toothpick, and attach it to the free chlorine. This newly
formed molecule containing chlorine and oxygen is
\
unstable. Use the extra white candy to represent a free atom
of oxygen. This can attract the other oxygen atom away from
the chlorine. Remove the white candy and its toothpick
from the green piece of candy and connect it to
the "free" white piece.
)
.0 a
Questions
0 At the end of this process, is the
chlorine atom attached to anything?
If this chlorine atom gets near more ozone, what will happen?
CO
it 2 I I I °,
%
w e What good things can you do now with all these candies?
.. .
Relating Science to
Math: In 1991, the size of the Antarctic ozone hole was estimated at 17.58 million
square km at its largest.
This was 13 times its size 10 years ago. How large was it 10 years ago?
3
9
Why study the Sun?
tor- Case
No.2
CLUES:
the Sun itself. The Sun's energy varies and could be
Another possible source of climate change is our star
modifying the chemistry and makeup of Earth's atmosphere.
The power of the Sun's energy is particularly visible when there are prominences, huge bright loops or arches
of gas that are evidence of violent solar storms. Solar flares are another kind of storm, but they are much
briefer. Although short, they are accompanied by increases in X-ray, gamma ray, and UV emissions by the Sun.
Variations in the strength of the solar wind also reflect changes in the Sun's output of energy. The solar wind is
a stream of high-energy particles released into space from the outermost layer of the Sun's atmosphere, the
corona. The solar wind is capable of interfering with radio and telephone communications on Earth. Sunspots,
which can be larger in area than Earth itself, are huge storms in the Sun's lower atmosphere, the photosphere.
The Sun's atmosphere above sunspots emits strong streams of X-rays, but the Sun's total brightness decreases
when large groups of sunspots appear on its surface.
All of these solar activities may affect Earth's climate, but we cannot know unless we study the Sun's energy over a long period of
time. The best plac to study the energy beaming from the Sun is in space, beyond the absorbing and reflecting effects of Earth's
atmosphere. Scientists made some of their major discoveries about the Sun while occupying America's first space station, Skylab, in
the 1970s. Researche;s have continued this important work over the years and now pursue it with ATLAS 2 and the Upper
Atmosphere Research Satellite, measuring the Sun's total energy output and comparing it with past measurements and future
particularly
calculations. ATLAS 2 scientists also evaluate changes in the intensity of individual parts of the solar spectrum
during this mission and others. (The solar spectrum is the range uf energy emitted by the Sun.)
infrared, visible, and UV radiation
Investigation A: Here, Spot.
While it is never safe to look directly at the Sun, sunspots can be viewed indirectly. Consult an almanac or
other science reference book to find out when sunspots are most likely to occur. During times of sunspot
activity, try this experiment.
materiaholitesh
paper plate
.1 straight pin
sheet of white typing paper
Procedure
Use the straight pin to make a hole in the center of the paper plate. With your back to the Sun, hold the plate so
that the sunlight can travel through the center hole. Focus the light onto the white paper, creating a small image
of the Sun. It may be necessary to slowly move the plate toward and then away from the white paper until you
obtain a clear image. The spots on the Sun should be visible as small, dark areas on the focused image.
Questions
0 What other solar event might be visible using this method?
it 90
4